package com.vn.egame.elazylite.ui;

import android.content.Context;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.View;
import android.view.View.MeasureSpec;

public class WrapContentHeightViewPager extends ViewPager {

	/**
	 * Constructor
	 *
	 * @param context
	 *            the context
	 */
	public WrapContentHeightViewPager(Context context) {
		super(context);
	}

	/**
	 * Constructor
	 *
	 * @param context
	 *            the context
	 * @param attrs
	 *            the attribute set
	 */
	public WrapContentHeightViewPager(Context context, AttributeSet attrs) {
		super(context, attrs);
	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
		super.onMeasure(widthMeasureSpec, heightMeasureSpec);

		// find the first child view
		View view = getChildAt(0);
		if (view != null) {
			// measure the first child view with the specified measure spec
			view.measure(widthMeasureSpec, heightMeasureSpec);
		}

		setMeasuredDimension(getMeasuredWidth(),
				measureHeight(heightMeasureSpec, view));
	}

	/**
	 * Determines the height of this view
	 *
	 * @param measureSpec
	 *            A measureSpec packed into an int
	 * @param view
	 *            the base view with already measured height
	 *
	 * @return The height of the view, honoring constraints from measureSpec
	 */
	private int measureHeight(int measureSpec, View view) {
		int result = 0;
		int specMode = MeasureSpec.getMode(measureSpec);
		int specSize = MeasureSpec.getSize(measureSpec);

		if (specMode == MeasureSpec.EXACTLY) {
			result = specSize;
		} else {
			// set the height from the base view if available
			if (view != null) {
				result = view.getMeasuredHeight();
			}
			if (specMode == MeasureSpec.AT_MOST) {
				result = Math.min(result, specSize);
			}
		}
		return result;
	}

}
